Method for Purifying Sophorolipid

Abstract

The present disclosure relates to a method of separating and purifying sophorolipids having improved physical properties such as unusual odor, color, and viscosity from oxidized and lactonic sophorolipids precipitate produced by culturing the genus Candida yeast fungus.

What is claimed is: 
     
         1 . A method for purifying sophorolipids, the method comprising:
 (1) ultrafiltering a sophorolipid precipitate from a culture fluid of the genus  Candida  yeast fungus;   (2) adding ethanol and activated carbon to the ultrafiltration residue, adsorbing it, and then removing the activated carbon and ethanol; and   (3) mixing the solution obtained in operation (2) with water to prepare an aqueous solution, and adjusting the pH of the aqueous solution to pH 5 or more and less than pH 7.   
     
     
         2 . The method of  claim 1 , wherein the ultrafiltering comprises the following:
 filtering with an ultrafiltration membrane having a molecular weight cutoff of 10,000 Da; and   filtering with an ultrafiltration membrane having a molecular weight cutoff of 1,000 to 3,000 Da.   
     
     
         3 . The method of  claim 1 , wherein the activated carbon is added in an amount of 5 to 15 parts by weight based on 100 parts by weight of ethanol. 
     
     
         4 . The method of  claim 1 , wherein the pH of the aqueous solution is adjusted by adding sodium hydroxide (NaOH).